Your trigger is written for one record at a time. Salesforce hands a trigger up to 200 records in a single call, so anything you do inside the loop — a SOQL query, a DML statement — runs 200 times and blows the per-transaction limit (100 queries, 150 DML statements).

The fix is the same every time: query once before the loop into a Map, and collect changes into a List you insert once after it.

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// one query, outside the loopMap<Id, Account> parents = new Map<Id, Account>([SELECT Id, Rating FROM Account]);for (Contact c : Trigger.new) {  c.Description = parents.get(c.AccountId).Rating;}

Test it with 200 records, not one [1] — a test that inserts a single row proves nothing about the case that broke.